Closing off large doorways often requires using a pair of doors, and the latching mechanisms used with such doors often dictate the sequence in which the doors must close to engage the latches. For example, one door may carry the latch mechanism while the remaining door must carry the receiver or striker mechanism. In a single-door doorway, the striker mechanism is mounted to the door frame and engages the latch mechanism when the door is closed. In the foregoing example, the door carrying the receiver or striker mechanism will be called the "lead door" meaning that this door must be closed first in order to correctly engage the latching mechanism. The remaining door carrying the latching mechanism will be called the "trailing door." Other door arrangements include an overlapping strip or astragal intended to close off any gap that may exist between the doors when they are in the fully closed position. The astragal must be mounted to the trailing door to allow the doors to close.
Door closing coordinators are well known in the art and serve the function of controlling the sequence in which the lead and trailing doors close. Door closing coordinators are commonly used in conjunction with doors that have some type of automatic door closing mechanism that will move a door from an open to a closed position after the door has been released. Carrying the foregoing example a bit further both the lead and trailing doors have automatic door closing mechanisms which will move the doors to a closed position and it is the coordinator's task to ensure that the lead door reaches a fully closed position before the trailing door regardless of the relative positions the doors are in when they are released, the speed with which each door closes, or other variables.
U.S. Pat. No. 4,429,492 (Imhoff) teaches and describes a door coordinator for a pair of oppositely hinged doors which controls the sequence in which the doors close by placing a stop proximate the hinge edge of the trailing door which props the door open sufficiently to allow the lead door to clear it and close. A release mechanism is contacted by the lead door which then allows the trailing door to close. Such door coordinators are preferably installed in the overhead portion of the door frame or are attached to the overhead portion of the door frame.
U.S. Pat. No. 5,033,234 (Simon et al) teaches and claims a door coordinator having a door stop which contacts the trailing door proximate the hinge edge of the door and a release mechanism which is contacted by the lead door intermediate the hinge edge and free edge of the lead door.
U.S. Pat. No. 4,949,505 (Cohrs) teaches and describes a door coordinator having a door stop which contacts the trailing door intermediate the hinge and free edges of the door and a release which, when contacted by the trailing door, releases the door stop. This patent uses a sliding carriage mechanism which extends between the door stop and the door release.
U.S. Pat. No. 5,651,216 (Tillmann) teaches and describes a door closer for a two-panel door with a closing sequence controlling mechanism having a door stop and door release, both of which are mounted to contact the doors proximate the hinge edges of the doors.
U.S. Pat. No. 5,582,472 (Lyons) teaches and describes a solvent storage cabinet having a door sequence control mechanism which allows the cabinet to close and latch in the event of a fire.
A product manufactured by the Triangle Brass Manufacturing Company of Los Angeles, Calif. designated as its 3092 Retracting Door Coordinator has a pair of arms of unequal length extending from an elongated housing. The longer of the two arms contacts the trailing door and holds it in an open position until the lead door contacts the shorter of the two arms, allowing the doors to close. The mechanism used with the Model 3092 Retracting Door Coordinator requires that the housing have a protuberance extending therefrom to enclose the timing mechanism.
The present invention relates to door coordinators of the general type illustrated by the Model 3092 coordinator that provide new, improved and more compact construction by enclosing the operating mechanism in a housing which is uniform in cross sectional area throughout and which is sufficiently compact to allow ease of installation while at the same time providing a narrow profile and attractive appearance.